Fall foliage in Washington

Washington’s color starts on the eastern crest of the Cascades and reaches the lowlands about a month later. Larch and aspen around Washington Pass, Slate Peak and the Okanogan highlands turn in the second week of October; the North Cascades, Picture Lake and the Rainier meadows follow in the middle of the month; the lowland maples and cottonwoods of Puget Sound, the Gorge and the San Juans finish at the end of October and into early November. Western larch, a deciduous conifer, is what gives the east side its yellow.

Those are the months when color is present somewhere in Washington, from its highest ground to its lowest. Any one location changes over a much shorter period than that.

Why the timing shifts from year to year

Shortening days start the process, so most places in Washington change at close to their usual time each year. Within the state, elevation and latitude account for most of the difference: higher and more northern ground generally changes first, and lower, sheltered ground last. Weather has more effect on how strong the color is than on when it appears. Cool nights and sunny days favor the reds, a dry summer mutes them, and a hard freeze or a windstorm can strip a slope in a day. What determines the timing goes through this in detail.

Nearby states

Fall color does not follow state lines. Washington borders:

• Idaho fall foliage
• Oregon fall foliage

Timing for a specific place

This page describes a whole state, which is about as precise as a season can be described in words. Conditions at one overlook on one weekend are a narrower question, and that is the one Fallcast answers: an expected period of color for a specific location, with a confidence attached, updated through the season as the trees change. It is coming to iPhone this fall.

Questions, or somewhere in Washington you would like covered? Write to fallcastapp@gmail.com.